Wilhelm dieterle



(No Model.) I -2 Sheets-Sheet 1.

. W. DIETERLE.

APPARATUS FOR PURIFYING NITRIC ACID.

No. 543,826. Patented J u1y30, 1895 ATTORNEYS.

(No Model.) 2 Sheets-Sheet 2. W. .DIETERLE.

APPARATUS FOR PURIFYING NITRIC ACID. No. 543,826. Patented July 30, 1895.

WITNESSES, /NVE NTOH Obj; I B) Y ATTQHNE rs "UNITED STATES PATENT OF ICE.

WILHELM DIETERLE, or FEUERBAOH, GERMANY.

APPARATUS FOR PUR IFYING NITRIC ACID.

SPECIFICATION forming part of Letters Patent; No. 543,826, dated July 30, 1895.

pp ication filed September 6, 1894- Serial No. 522,236. (No model.)

To all whom it may concern:

Be itknown that I, WILHELM DIETERLE, a subject of the King of Wiirtemberg, residing at Feuerbach, near Stuttgart, Germany, have invented certain new and useful Apparatus for Purifying Nitric Acid, of which the followingis a specification.

The present invention relates to an 'improved apparatus for purifying nitric acid; and the object of the invention is to provide for theprodnction of nitric acid free of halogen and nitrous acid by means of a cooling apparatus permitting of rapid and perfect escape of the low oxides.

The apparatus is shown in the accompanying drawings, in which Figure 1 is a cross-section showing worms or serpentine pipes of clay. Fig. 2 is a plan view of the same. Fig. 3 is a cross-section of modification, and Fig. 4 is a plan view of A in the drawings represents the generating receptacle containing the mixture, into which air or other indiiferent gas is forced by means of a tube B. From this receptacle the air laden with nitric acid vapors is conducted by a pipe (1 to a cooler or condenser composed of a series of coilsof pipe y, formlng a worm.

A tube 19 is connected to the coilsof the worm by small inclined branch pipes a, and

terminates in asuitable reservoir, it being provided with a siphon-cock, as shown at h.

The lower coil of the cooler or condenser communicates through a suitable pipe with the receiver K for the purified nitric acid.

The air laden with the nitric acid and the impurities passes to the cooler, and condensation thereof takes place in the upper coils; and in order that this condensation may more tranquilly and effectually take place the'said upper coils (three in the drawings) are not in communication withthe tube or canal b. By this means a nitric acid free of halogen and nitrous acid is prodncedwithin the cooler, and in this quality the nitric acid is then conveyed to the receiver.

It frequently happens'that smallquantities of the liquid nitric acid are carried bodily from the receptacle A into the condenser when the air is first introduced into the receptacle A before the removal of the chlorine andthe bleaching have taken place.

cooler are still weakly colored, and show a small reaction of chlorine. For collecting this impure nitric acid a branch pipe is introduced betweenthecooler and receiver, siphoncocksfand 9 being provided, so that the first nitric acid may be drawn oif through siphoncock f, and afterward this cock closed and the cock g opened to let the pure acid pass directly-to the receiver. The impure acid thus collected may be returned to the receptacle A. It is impossible, also, during distillation to prevent small quantities of the vapors of nitric acid passing along with the air through the tubes at to the canal b, wherethey are condensed. In order to collect this a reservoir may be provided, in connection with the lower end of tube 1), with asiphon-cock h. In the drawings this reservoir is shown as formed by extending the tube or canal b a short'distance below the lower coil of the condenser, and the acid condensing here may be permitted to continuously drip off and thus be collected, or the cock may be closed and the acid caused to overflow through the lower branch 0, and coily to the receiver K.

The siphon-cocks permit advantageously of tests being made during operation.

It will be understood that the acid condensing within the canal is stronger than the acid already condensed within the cooler. As

adjacent thereto, and tubes connecting the canal with said coils, substantially as described.

2. In combination with an evaporating receptacle, a condenser comprising a series of The quantities' of nitric acid thus carried into the IOC , coils, a vertical canal adjacent thereto, a se berg, Germany, this 26th day of July, in the ries of inclined tubes connecting the canal year 1894. with said coils, a reservoir and si hon cock s w 1 1 at the lower end of said canal, add a tube ILHELM Dnfl LRLE' leading from the condenser to a receiver for Witnesses: the purified acid, substantially as described. ERNST DIETRICH, Signed at Stuttgart, Kingdom of Wiirtem- PAUL DRISCHER. 

